DIFFUSION-COEFFICIENTS OF OXYGEN AND HEMOGLOBIN MEASURED BY FACILITATED OXYGEN DIFFUSION THROUGH HEMOGLOBIN-SOLUTIONS

Diffusion coefficients of oxygen (D-O2) and hemoglobin (D-Hb) were obt ained from measuring the oxygen flux through thin layers of hemoglobin solutions at 20 degrees C. The liquid layers were supported by a memb rane and not soaked in any filter material. Oxygen fluxes were measure d from the changes in oxygen partial pressure in the gas phases at bot h sides of the layer. A mathematical treatment is presented for correc t evaluation of the measurements. Measurements were done for bovine an d for human hemoglobin. Hemoglobin concentrations (C-Hb) were between 11 and 42 g/dl, which covers the concentrations in the erythrocyte. Bo th D-O1 and D-Hb could be fitted to the empirical equation D = D-0(1 - C-Hb/C-1)10(-CHb/C2). The following parameters were obtained: D-0 = 1 .80 x 10(-9) m(2)/s, C, = 100 g/dl, C-2 = 119 g/dl, for oxygen and D-0 = 7.00 x 10(-11) m(2)/s, C-1 = 46 g/dl, C-2 = 128 g/dl, for hemoglobi n. No difference between the diffusion coefficients of bovine or human hemoglobin was found. The diffusion coefficients of hemoglobin were h igher than most values reported in the literature, probably because in this study the mobility of hemoglobin was not hindered by surrounding filter material.